The invention relates to an expansible plug, particularly to an expansible plug used for anchoring to solid or hollow building materials.
A known expansion plug has expansion elements formed on a shank of the plug and is provided with a screw hole for receiving a fixing screw that displaces the expansion elements laterally as it is screwed into the screw hole.
Expansible plugs made of plastic material are also known, which have essentially two expansible arms that are pressed laterally outwards as a fixing screw is screwed into them thereby forcing them to expand laterally. When an expansible plug of this kind is inserted in a hole in masonry, then the arms of the expansible plug, which may also be referred to as expansion elements, are pressed against the wall of the drilled hole, thus securing the expansion plug firmly in the drilled hole. These expansible plugs achieve very good holding values in hard solid building materials. However in softer building materials and in honeycomb bricks, the use of these known expansible plugs is only possible to a limited extent.
Universally usable expansible plugs are also known which have a sleeve-shaped end opposite the plug head which protrudes from the hole in which they are inserted. The fixing screw is inserted into the sleeve-shaped end. In solid building material, this universal plug acts like the above-described expansible plug, and presses with its arms against the wall of the drilled hole. In a hollow building material, on the other hand, the sleeve-shaped end is moved towards the plug head by turning the fixing screw, the arms opening wide apart in the cavity and engaging the rear side of a member defining the cavity. In building materials with dispersed cavities or cavities with bordering cross members the structure of the material may prevent the arms from opening out, so that the expansible plug in this situation braces against the wall of the drilled hole.